CONTENTS 



No. 1. SEPTEMBER, 1919 



H. E. Jordan. The histology of the umbilical cord of the pig, with special reference to 

 the vasculogenic and hemopoietic activity of its extensively vascularized connective 

 tissue. Fifteen figures 1 



Henry A. Murray Jr. The development of the cardiac loop in the rabbit, with especial 

 reference to the bulboventricular groove and origin of the interventricular septum. 

 Seven figures 29 



Frank Blair Hanson. The ontogeny and phylogeny of the sternum. Twelve plates 



(forty-nine figures) 41 



George W. Corner. On the origin of the corpus luteum of the sow from both granulosa 

 and theca interna. Twenty-six figures 117 



No. 2. NOVEMBER, 1919 



Harold J. Cooper. The hypophysis cerebri of the California ground-squirrel, Citellus 



beechyi (Richardson). Eleven figures 185 



Ralph Dougall Lillie. The early histogenesis of the blood in Bufo halophilus Baird 



and Girard. Seven figures 209 



Henry H. Donaldson. Quantitative studies on the growth of the skeleton of the albino 



rat. Twenty-three charts 237 



No. 3. JANUARY, 1920 



Leslie B. Arey. The origin, growth, and fate of osteoclasts and their relation to bone 

 resorption. Twenty-four figures 315 



S. Sagtjchi. Studies on the glandular cells of the frog's pancreas. Five plates 347 



Frederic T. Lewis. The course of the Wolffian tubules in mammalian embryos. Thir- 

 teen figures 423 



William H. F. Addison. Histological study of the spleen of the rabbit under height- 

 ened phagocytic activity. Six figures (one plate) 437 



